I was struggling to get from the map api pages to where I could find a map api key. Google have recently restructured the way they provide API keys.
If you search in google for "google api console" you should find what you're looking for.
Alternatively, here is the link to the console root:
https://code.google.com/apis/console/[
^]
Click the services link, then click the off switch against the translate api to enable the service and generate a key.